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Types of 5-HTP: Forms & Bioavailability

Evidence:Moderate
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This content is for informational purposes only and does not constitute medical advice. Statements about dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary — consult your healthcare provider before starting any supplement. Full disclaimer

Forms Comparison

FormBioavailabilityBest For
5-HTP (Griffonia simplicifolia extract)HighStandard supplemental form; crosses blood-brain barrier freely
Enteric-coated 5-HTPHighReduced GI side effects; delayed release for sleep applications

5-HTP (Griffonia simplicifolia extract)

Bioavailability: High. Best for: Standard supplemental form; crosses blood-brain barrier freely.

Enteric-coated 5-HTP

Bioavailability: High. Best for: Reduced GI side effects; delayed release for sleep applications.

Full 5-HTP Guide

References

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  2. RCTCaruso I, Sarzi Puttini P, Cazzola M, Azzolini V. (1990). Double-blind study of 5-hydroxytryptophan versus placebo in the treatment of primary fibromyalgia syndrome. Journal of International Medical Research. DOI PubMed
  3. RCTLi S, Sutanto CN, Xia X, Kim JE (2025). The Impact of 5-Hydroxytryptophan Supplementation on Cognitive Function and Mood in Singapore Older Adults: A Randomized Controlled Trial.. Nutrients. DOI PubMed
  4. RCTSutanto CN, Xia X, Heng CW, Tan YS, et al. (2024). The impact of 5-hydroxytryptophan supplementation on sleep quality and gut microbiota composition in older adults: A randomized controlled trial.. Clinical nutrition (Edinburgh, Scotland). DOI PubMed
  5. Evans C, Mekhail V, Curtis J, Czartoryski P, et al. (2023). The Effects of 5-HTP on Body Composition: An 8-Week Preliminary RCT.. Journal of dietary supplements. DOI PubMed
  6. Zamoscik V, Schmidt SNL, Bravo R, Ugartemendia L, et al. (2021). Tryptophan-enriched diet or 5-hydroxytryptophan supplementation given in a randomized controlled trial impacts social cognition on a neural and behavioral level.. Scientific reports. DOI PubMed
  7. van der Burg KP, Cribb L, Firth J, Karmacoska D, et al. (2020). EPA and DHA as markers of nutraceutical treatment response in major depressive disorder.. European journal of nutrition. DOI PubMed
Show 2 more references
  1. Sarris J, Byrne GJ, Stough C, Bousman C, et al. (2019). Nutraceuticals for major depressive disorder- more is not merrier: An 8-week double-blind, randomised, controlled trial.. Journal of affective disorders. DOI PubMed
  2. Sauer H, Mack I, Kohler S, Siegle S, et al. (2014). The effects of 5-hydroxytryptophan in combination with different Fatty acids on gastrointestinal functions: a pilot experiment.. Gastroenterology research and practice. DOI PubMed